(1) Field of the Invention
The present invention relates generally to strain reliefs for cable connections and more particularly to a split design, clamping mechanism providing positive strain relief in a dynamic environment.
(2) Description of the Prior Art
Cable connections are susceptible to stress and damage whenever the connection is handled or the cable is pulled or twisted. In order to minimize this stress, various types of strain relief mechanisms are incorporated into the connections. U.S. Pat. No. 3,387,254 to Wheeler recites a device consisting of a continuous plastic belt which fits over the conductors extending from a conventional wall plug. The belt has slots on one end allowing the conductors to protrude past the plastic so that they be inserted into a wall receptacle. A metal strip is crimped over the other end of the belt and the cord to mechanically grip the cord at a position spaced from the plug end such that a small loop of cord is formed between the crimped end and the plug. When the cord is pulled, as when removing the plug from the receptacle, the belt transmits the forces on the cord to the plug housing. The device is not applicable to cables having large diameters which cannot be looped or those requiring a more secure method of attaching the strain relief device to the connector. U.S. Pat. No. 5,006,960 to Kallin et al. recites a somewhat similar strain relief method in that a loop in the cable provides strain relief for the connection. U.S. Pat. No. 4,863,396 to Johnson recites a strain relief clamp assembly having a female cylindrical component with a plurality of radially directed bearing access ports, a ball bearing and a biasing means. The inside surface of the female component has a concentric groove with an access channel to the outside surface. One side portion of a locking wire is inserted through the access channel. The clamp has a male compression ring component having a matching concentric groove on its outside surface for receiving the opposite side portion of the locking wire and further has a plurality of spaced apart ball bearing depressions. The male component is inserted into the female component and is locked thereto by the locking wire. Relative rotation between the female and male components is prevented by the female component ball bearing held in one of the male component depressions. The male component carries a clamp which is tightened about the wire bundle passing through the male component. Where rotation of one component relative to the other is not required, an assembly not having the complexity of the Johnson assembly would be advantageous. In some applications it is necessary for the cable connection to remain watertight. For example, outboard sensor housings in a marine environment typically have rubber boots bonded to the metal housing which surround the sensor cable connection when attached to the housing. Connector guards are provided adjacent the rubber boots to prevent foreign objects from striking and breaking the sensor cable connection. While positive locking plugs are used to ensure the sensor cable does not loosen from the housing, movement and twisting of the cable results in stressing the rubber to metal bond. Over time and repeated stress, this bond fails. Failure of the bond results in water entering the connection causing the sensor to fail.